MPs have taken evidence from the Metropolitan Police's Acting Deputy Commissioner John Yates on the phone-hacking allegations.
Mr Yates rejected allegations, made by a Labour MP, that he misled Parliament over the phone hacking allegations.
Chris Bryant MP claimed in a Commons debate two weeks ago that Mr Yates, had misled the Home Affairs Committee last September when he said only 10 to 12 people had had their mobile phone messages intercepted.
Appearing before the Culture Committee on 24 March 2011, Mr Yates said Mr Bryant had made "several assertions that are not correct".
The row hinges on the legal definition of phone hacking.
Mr Bryant said Mr Yates had misled the committee about the legal advice he received and used a narrow definition of phone hacking in order to suggest there were only a few victims.
Mr Yates rejected that claim, telling the committee that to prove phone hacking, the prosecution had to show that a voicemail had been intercepted before the owner had listened to it.
"On this basis, I advised that there may in fact only perhaps be 10 to 12 victims against whom we can actually prove an offence," he said.
Mr Yates maintained that this was the advice he had received from the CPS.
Mr Yates also said that "perhaps more could have been done" to investigate the allegations, which first surfaced in 2005, but rejected claims of deliberately suppressing evidence of wrongdoing by journalists and executives.
Mr Yates had offered to face MPs to "rebut" claims he misled Parliament by suppressing the full extent of the scandal.
Four alleged phone-hacking victims have reached out-of-court settlements with the newspaper, including celebrity publicist, Max Clifford, who received a reported £1m.